Ok… so I'm experimenting with tubes to warm my Krank Rev Jr. up. I settled for JJ ECC83S's in V1 and V2 and a JJ ECC803S for the PI, but I have not decided on a set of power tubes yet. The Krank is a cool amp to experiment with because it has a cathode-biased power section. The manual states I can just drop in any pair of 6V6 or 5881/6L6 tubes in there without making any adjustments. However, the headshell is really small, so I'm pretty limited when it comes to choices of 6L6's. I have tried a pair of JJ 6V6S, Sovtek 5881/6L6WGC, Tung Sol 6L6GC-STR, and Tung Sol 5881. I was going throw the Sovteks in this shootout as well, but unfortunately, I dropped one and destroyed it when doing this shootout, so they didn't make it. https://dl.dropboxusercontent.com/u/315457/JJ6V6SvTungSol6L6GC-STRvTungSol5881.mp3 Same settings and mic position for all. I reamped the same performance too. First is the JJ, then the TS 6L6, and last the 5881. So I mixed them to more or less the same level so that they could be compared more directly. The 5881 was way louder than the other two. I did it by ear and quickly, so it may be a bit off, but if you'd like, I can upload the tracks unmixed. I also have high shelf just dropping 1dB in the high-end because I dialed in the amp for the warmest-sounding tube and the rest sounded way too bright, lol.